" wrote in
:
On Mon, 27 Dec 2010 07:13:36 -0600, Jim Yanik
wrote:
" wrote in
m:
On Sun, 26 Dec 2010 16:02:42 -0500, wrote:
On Sun, 26 Dec 2010 12:41:26 -0600, "
wrote:
Probably parallel strings of LEDs.
*Series* strings. Parallel does nothing but cause more trouble.
;-)
OK the science comes fast around here
I took a flashlight apart.
It appears they use a 4.5v LED, 9 in parallel with NO resistor at
all. The internal resistance of 3 AAA cells seems to be the limiter
I've seen that too; a very poor design. There is nothing to
current-share across the LEDs. Counting on the internal resistance
of a battery is really ****-poor.
hey,they were FREE,including the batteries. ;-)
HF gives them away free with a coupon from their many ads.
HF buys their stuff from where? ;-)
Communist China. :-)
of course,they don't use the batteries efficiently.
The problem that I have with it is counting on the internal resistance
of the battery. As long as the same *type* of battery is used there
isn't a real problem. If another type is used things can go very
wrong.
they come with "heavy duty" AAA carbon-zincs,but I also tried alkalines
with them,and they were brighter with the carbon-zincs. they may be
UNDERdriven.
I still have two more coupons for free ones,and the local HF store is only
a short walk away!
Plus,I see the ads are still coming out with the coupons.
they're nice little flashlights for the "price"! B-)
--
Jim Yanik
jyanik
at
localnet
dot com